Register Access in Distributed Virtual Bridge Environment

1. An apparatus comprising: a plurality of server computers; a plurality of distributed bridge elements in communication with the plurality of server computers, wherein each distributed bridge element is configured to access a register in response to receiving a data frame that includes a register access request; and a controlling bridge configured to control the plurality of distributed bridge elements and to generate and communicate the data frame to at least one of the plurality of bridge elements, wherein the data frame includes a sequence number associated with the register access request, and wherein the controlling bridge is configured to use the sequence number to confirm that the data frame was delivered to the bridge element.

2. The apparatus of claim 1 , wherein the register is included within a bridge element of the plurality of bridge elements.

3. The apparatus of claim 1 , further comprising a non-bridge element node that includes the register.

4. The apparatus of claim 1 , further comprising a main register ring coupled to the plurality of bridge elements, wherein the main register ring includes a token protocol.

5. The apparatus of claim 1 , wherein the register access request includes at least one of a load and a store operation.

6. The apparatus of claim 1 , wherein a bridge element of the plurality of bridge elements is configured to store the sequence number in a memory.

7. The apparatus of claim 1 , wherein the controlling bridge is configured to store the sequence number in a memory.

8. The apparatus of claim 7 , wherein the memory is configured as a first-in, first-out memory.

9. The apparatus of claim 1 , wherein the controlling bridge is configured to select a bridge element of the plurality of bridge elements to communicate the register access request to a non-bridge element node that includes the register.

10. The apparatus of claim 1 , wherein at least one of a bridge element of the plurality of bridge elements and the controlling bridge stores a count of successfully completed register access requests.

11. The apparatus of claim 1 , wherein a bridge element of the plurality of bridge elements is configured to communicate status information associated with the register access request to the controlling bridge.

12. The apparatus of claim 1 , wherein the controlling bridge is configured to resend the data frame in response to determining that an error occurred with respect to at least one of the communication of the data frame and an execution of the register access request.

13. The apparatus of claim 1 , wherein at least one of the controlling bridge and a bridge element of the plurality of bridge elements are configured to initiate a semaphore operation prior to execution of the register access request.

14. A method of performing a register access, the method comprising: receiving a data frame at a bridge element of a plurality of bridge elements in communication with a plurality of server computers, wherein the data frame includes a register access request and is forwarded from a controlling bridge in communication with the plurality of bridge elements; and accessing a register and initiating execution of the register access request in response to receiving the data frame, wherein the data frame includes a sequence number associated with the register access request, and wherein the controlling bridge is configured to use the sequence number to confirm that the data frame was delivered to the bridge element.

15. The method of claim 14 , further comprising accessing the register using a token.

16. The method of claim 14 , further comprising accessing the register without using a token, wherein the register is included within the bridge element.

17. The method of claim 14 , further comprising communicating status information associated with the register access request to the controlling bridge.

18. A program product for accessing a register, the program product comprising: a computer readable storage medium having computer readable program code embodied therewith, the computer readable program code comprising program instructions resident at a bridge element of a plurality of bridge elements in communication with a plurality of server computers, the program instructions configured to receive from a controlling bridge a data frame that includes a register access request, to access a register, and to initiate execution of the register access request in response to receiving the data frame, wherein the controlling bridge is configured to select the bridge element to communicate the register access request to a non-bridge element node that includes the register.

19. The program product of claim 18 , wherein the data frame is addressed to the non-bridge element node.

20. The program product of claim 18 , wherein the non-bridge element node is a partition, an integrated switch router, or a transport layer module.